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141.
142.
新注射吸毒者及长期注射吸毒者共用针具的影响因素分析 总被引:1,自引:1,他引:0
目的 了解新注射吸毒者和长期注射吸毒者共用针具的影响因素.方法 对四川省注射吸毒者进行社区横断面调查.结果 3852名被调查者中,注射吸毒史<1年、1~3年和>3年者最近6个月共用针具比例依次为19.9%、29.1%和36.3%.注射吸毒<1年的被调查者共用针具的独市影响因素包括女性、少数民族、注射吸毒频率高、共用注射器/针头以外其他吸毒用具、有非同定性伴、固定性伴注射吸毒、未自愿做过艾滋病检测、招募年、招募地区;注射吸毒1~3年的被凋查者共用针具的独立影响因素包括文化程度低、注射频率高、共用注射器/针头以外其他吸毒用具、有非固定性伴、固定性伴注射吸毒、未使用安全套、未参与技能培训、招募年、招募地区;注射吸毒>3年的被调奋者共用针具的独立影响因素包括文化程度低、注射频牢高、共用注射器/针头以外其他吸毒用具、有非同定性伴、有商业性伴、固定性伴注射吸毒、未使用安全套、未参与针具交换、招募年、招募地区.结论 新注射吸毒者和长期注射吸毒者共用针具及无保护性行为比例均较高,长期注射吸毒者较新注射吸毒者有更多共用针具行为和无保护性行为,针对两类人群的干预应有不同侧重. 相似文献
143.
Yang X Jin T Press R Quezada HC Fredrikson S Zhu J 《Journal of neuroimmunology》2008,200(1-2):129-132
The proportion of peripheral blood mononuclear cells (PBMCs) expressing TNF-alpha and its receptors (TNFR1, TNFR2) and the serum concentrations of its soluble forms were analyzed by FACS and ELISA in the patients with chronic inflammatory demyelinating polyneuropathy (CIDP) and in controls. Elevated levels of TNFR2 were observed on blood T cells in CIDP and idiopathic polyneuropathy. Low levels of TNFR1 were detected on monocytes in the subgroup of patients with CIDP examined after treatment with intravenous immunoglobulin. However, the proliferative activity of PBMCs in CIDP was not influenced by soluble recombinant TNFR1. Our limited data suggested the exact role of TNF-alpha and its receptors need to study further in CIDP, as well as in idiopathic neuropathies. 相似文献
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145.
Distinct roles of integrins alpha6 and alpha4 in homing of fetal liver hematopoietic stem and progenitor cells 总被引:2,自引:0,他引:2 下载免费PDF全文
Qian H Georges-Labouesse E Nyström A Domogatskaya A Tryggvason K Jacobsen SE Ekblom M 《Blood》2007,110(7):2399-2407
Homing of hematopoietic stem cells (HSCs) into the bone marrow (BM) is a prerequisite for establishment of hematopoiesis during development and following transplantation. However, the molecular interactions that control homing of HSCs, in particular, of fetal HSCs, are not well understood. Herein, we studied the role of the alpha6 and alpha4 integrin receptors for homing and engraftment of fetal liver (FL) HSCs and hematopoietic progenitor cells (HPCs) to adult BM by using integrin alpha6 gene-deleted mice and function-blocking antibodies. Both integrins were ubiquitously expressed in FL Lin(-)Sca-1(+)Kit(+) (LSK) cells. Deletion of integrin alpha6 receptor or inhibition by a function-blocking antibody inhibited FL LSK cell adhesion to its extracellular ligands, laminins-411 and -511 in vitro, and significantly reduced homing of HPCs to BM. In contrast, the anti-integrin alpha6 antibody did not inhibit BM homing of HSCs. In agreement with this, integrin alpha6 gene-deleted FL HSCs did not display any homing or engraftment defect compared with wild-type littermates. In contrast, inhibition of integrin alpha4 receptor by a function-blocking antibody virtually abrogated homing of both FL HSCs and HPCs to BM, indicating distinct functions for integrin alpha6 and alpha4 receptors during homing of fetal HSCs and HPCs. 相似文献
146.
Cserni G Bianchi S Vezzosi V Arisio R Bori R Peterse JL Sapino A Drijkoningen M Kulka J Eusebi V Foschini MP Bellocq JP Marin C Thorstenson S Amendoeira I Reiner-Concin A Decker T 《European journal of cancer (Oxford, England : 1990)》2007,43(9):1407-1414
This study aimed at identifying factors related to sentinel lymph node (SLN) involvement in patients with tubular, cribriform, mucinous or papillary breast carcinoma and those related to non-SLN metastases if an SLN was positive. Multivariate analyses involved logistic and stepwise regressions. The SLNs harboured metastases in 85 of 572 cases, 78 of whom underwent axillary dissection; 19 presented non-SLN positive disease. Lack of lymphovascular invasion, a tumour size < or = 10 mm and a single SLN removed were the factors predicting an SLN metastasis rate <10%, and patients with these features could be candidates for no surgical axillary staging. A positive SLN proportion of < or = 50% and no lymphovascular invasion were associated with a <10% rate of non-SLN invasion; patients with a positive SLN and these features could be candidates for the omission of completion axillary dissection. The opposite presentation of these factors would mandate SLN biopsy and axillary dissection, respectively. 相似文献
147.
148.
Pfenninger CV Roschupkina T Hertwig F Kottwitz D Englund E Bengzon J Jacobsen SE Nuber UA 《Cancer research》2007,67(12):5727-5736
Human brain tumor stem cells have been enriched using antibodies against the surface protein CD133. An antibody recognizing CD133 also served to isolate normal neural stem cells from fetal human brain, suggesting a possible lineage relationship between normal neural and brain tumor stem cells. Whether CD133-positive brain tumor stem cells can be derived from CD133-positive neural stem or progenitor cells still requires direct experimental evidence, and an important step toward such investigations is the identification and characterization of normal CD133-presenting cells in neurogenic regions of the embryonic and adult brain. Here, we present evidence that CD133 is a marker for embryonic neural stem cells, an intermediate radial glial/ependymal cell type in the early postnatal stage, and for ependymal cells in the adult brain, but not for neurogenic astrocytes in the adult subventricular zone. Our findings suggest two principal possibilities for the origin of brain tumor stem cells: a derivation from CD133-expressing cells, which are normally not present in the adult brain (embryonic neural stem cells and an early postnatal intermediate radial glial/ependymal cell type), or from CD133-positive ependymal cells in the adult brain, which are, however, generally regarded as postmitotic. Alternatively, brain tumor stem cells could be derived from proliferative but CD133-negative neurogenic astrocytes in the adult brain. In the latter case, brain tumor development would involve the production of CD133. 相似文献
149.
Erlend Stav Ståle Walderhaug Marius Mikalsen Sten Hanke Ivan Benc 《International journal of medical informatics》2013,82(11):e269-e293
IntroThe proper use of ICT services can support seniors in living independently longer. While such services are starting to emerge, current proprietary solutions are often expensive, covering only isolated parts of seniors’ needs, and lack support for sharing information between services and between users. For developers, the challenge is that it is complex and time consuming to develop high quality, interoperable services, and new techniques are needed to simplify the development and reduce the development costs.This paper provides the complete view of the experiences gained in the MPOWER project with respect to using model-driven development (MDD) techniques for Service Oriented Architecture (SOA) system development in the Ambient Assisted Living (AAL) domain.MethodTo address this challenge, the approach of the European research project MPOWER (2006–2009) was to investigate and record the user needs, define a set of reusable software services based on these needs, and then implement pilot systems using these services. Further, a model-driven toolchain covering key development phases was developed to support software developers through this process. Evaluations were conducted both on the technical artefacts (methodology and tools), and on end user experience from using the pilot systems in trial sites.ResultsThe outcome of the work on the user needs is a knowledge base recorded as a Unified Modeling Language (UML) model. This comprehensive model describes actors, use cases, and features derived from these. The model further includes the design of a set of software services, including full trace information back to the features and use cases motivating their design. Based on the model, the services were implemented for use in Service Oriented Architecture (SOA) systems, and are publicly available as open source software. The services were successfully used in the realization of two pilot applications. There is therefore a direct and traceable link from the user needs of the elderly, through the service design knowledge base, to the service and pilot implementations.The evaluation of the SOA approach on the developers in the project revealed that SOA is useful with respect to job performance and quality. Furthermore, they think SOA is easy to use and support development of AAL applications. An important finding is that the developers clearly report that they intend to use SOA in the future, but not for all type of projects. With respect to using model-driven development in web services design and implementation, the developers reported that it was useful. However, it is important that the code generated from the models is correct if the full potential of MDD should be achieved.The pilots and their evaluation in the trial sites showed that the services of the platform are sufficient to create suitable systems for end users in the domain.ConclusionsA SOA platform with a set of reusable domain services is a suitable foundation for more rapid development and tailoring of assisted living systems covering reoccurring needs among elderly users. It is feasible to realize a tool-chain for model-driven development of SOA applications in the AAL domain, and such a tool-chain can be accepted and found useful by software developers. 相似文献